Two position snap action operator



Aug. 1951 G. E. LUSK ET AL 2,995,043

TWO POSITION SNAP ACTION OPERATOR 3 Sheets-Sheet 1 Filed June 20, 1960Aug. 8, 1961 G. E. LUSK ETAL TWO POSITION SNAP ACTION OPERATOR 3Sheets-Sheet 2 Filed June 20, 1960 INVENTORSA Georgsi. Zas/a BYcZ/fVa/ZHeie/Y 3 M Ma Aug. 8, 1961 LUSK A 2,995,043

TWO POSITION SNAP ACTION OPERATOR Filed June 20, 1960 3 Sheets-Sheet 5INVENTOR5- Geo/ye [Z115]:

Unite ttes Patent Ofiice Patented Aug. 8, 1961 TWO POSITION SNAP ACTIONOPERATOR George Edward Lusk, Downers Grove, and Richard H.

Van Meter, South Holland, Iil., assignors to G & W

Electric Specialty Company, Blue Island, 111., a corporation of IllinoisFiled June 20, 1960, Ser. No. 37,475 9 Claims. (CI. 74-97) The inventionrelates to mechanical operators for electric switches and has referencein particular to a switch operator of the toggle type having oscillatingsnap action for performing the switching operation.

It is desirable from the standpoint of safety of the switchman toprovide a mechanical operator for actuating electric switches, and thisis especially so as regards large switches which handle electriccurrents of high amperage. Once the switchman has provided the necessaryenergy for the device to perform a switching operation, the mechanicaldevice completes the actual current interruption and at the desired rateof speed regardless of any additional action on the part of theswitchman. Furthermore, once the device takes over the switchingoperation, the switchman cannot slow down, stop or reverse the action. Aswitch operator capable of providing this type of function is said to betrip free.

The invention has for its main objective the provision of a mechanicalswitch operator of the toggle type which will be trip free and whereinthe coil springs for the toggle structure will be fully compressed forstoring energy therein to the maximum extent before tripping takes placeto actuate the operating shaft of the switch.

A more particular object is to provide a switch operator of the toggleaction type and wherein respective parts of the toggle are provided withcams which coact in a manner to prevent switch operation until the coilsprings of the toggle are fully compressed. Accordingly, the switchoperator of the invention stores the maximum amount of energy in thecoil springs of the toggle arrangement so that when released it willrotate the switch operating shaft in a positive manner and at a highrate of speed.

A further object is to provide a mechanical switch operator of thetoggle type wherein latch means carried by one part of the toggle coactWith cam elements carried by the other part of the toggle in a manner toprevent unintentional or accidental rotation of the switch operatingshaft.

Another object of the invention is to provide a two position snap actionswitch operator which will be relatively simple in design embodying aminimum of parts and which can be economically manufactured.

With these and various other objects in view, the invention may consistof certain novel features of construction and operation, as will be morefully described and particularly pointed out in the specification,drawings and claims appended thereto.

In the drawings which illustrate an embodiment of the device and whereinlike reference characters are used to designate like parts- FIGURE 1 isa front elevational view illustrating the mechanical switch operator ofthe invention in a midposition as regards the carriage yoke of thetoggle structure;

FIGURE 2 is a vertical sectional view taken substantially along line 2-2of FIGURE 1;

FIGURE 3 is a fragmentary sectional view similar to FIGURE 2 but showingthe carriage yoke in a position where the fully compressed coil springstructure is about to be released for tripping the toggle and rotatingthe operating shaft of the switch device;

FIGURE 4 is a fragmentary sectional view similar to FIGURE 3 but showingthe position of the toggle parts following release and which hasproduced rotation of the switch operating shaft in a counterclockwisedirection;

FIGURE 5 is a fragmentary sectional view similar to FIGURE 4 but showingthe position of the toggle parts just before release for producingclockwise rotation of the switch operating shaft;

FIGURE 6 is an end elevational view of the supporting frame shown inFIGURE 7;

FIGURE 7 is a front elevational view of the supporting frame for theswitch operator;

FIGURE 8 is a view of the right hand end of the supporting frame; and

FIGURE 9 is a front elevational view of the carriage yoke.

Referring in particular to FIGURE 1, it will be seen that the operatingshaft of the electric switch mechanism is indicated by numeral 10 andthat the operating shaft of the switch operator is indicated by numeral11, said shaft 11 extending through and beyond the supporting structure12 to which the supporting frame 13 of the operator is secured. Theconstruction and shape of frame 13 is best shown in FIGURE 7 wherein itwill be observed that the same is substantially a yoke including a pairof upstanding supports 14 and 15, having journalling portions 16 and 17at their respective ends and intermediate journalling openings 18 andL9. The support 14 is wider at an intermediate location than at its baseand the spaced extremities of said intermediate part are formed toprovide the spaced stops 20 and 21. Upright support 15 has the openings22 therein, and this sup port is bolted to the structure 12 by the bolts23.

The operating shaft 11 is journalled in the fixed supporting frame 13 bythe journ-alling portion 17, and said end of the shaft 11 is fixed tothe carriage yoke 25 as at 26. The yoke essentially includes the arms 27and 28, a top connecting part 29 and the cams 30 and 31 which are formedintegrally with the yoke adjacent the lower end of the arms. Cam 36 isformed on arm 27 and the same faces in one direction, whereas cam 31 isformed on arm 28 and the same faces in an opposite direction. A studshaft 32 is fixed to arm 27 at 33 and the stud shaft extends into and isjournalled by the portion 16.

The base toggle member 34 is also in the form of a yoke having a base35, a pair of arms 36 and 37 each terminating in a journalling portionsuch as 38. The base 35 is fixed at 39 to the switch operating shaft 10,the said shaft being journalled in the intermediate journalling openings18 and 19 of the frame structure. The spring supporting base member 40is carried by the base toggle member 34 by means of laterally extendingstud shafts integral with the base member 40 and which are respectivelymounted in the portions 38 so as to extend through and project beyondthe same. The projecting ends of the stud shafts provide the camfollowers 41 and 42.

The coil spring structure of the toggle arrangement includes a pair ofcoil springs 43 and 44, each being supported at their base by the member40. The upper end of each coil spring engages the toggle plate 45 havingthe nose portion 46, and which is mounted in the connecting part 29' ofthe carriage yoke, the said connecting part on its underside is shapedat 47 to anchor the nose portion and thus the plate for pivotalmovement. Said toggle plate 45' is integral with a rod 48 extendingcentrally through the coil springs and said rod also extends centrallythrough an opening in the base support member 40 to project apredetermined distance below the same. The construction of the carriageyoke and base supporting member is such as to locate the cam followers41 and 42 in operative relation with the cams 30 and 31. Also, it willbe observed that the base toggle member 34 is limited in its oscillatingmovements by the stops 20 and 21 which are located in the path of thearm 36.

In order to prevent a torque being applied to the switch operating shaftsuch as might rotate the shaft and override the toggle switch operator,the invention includes a spring loaded blocking lever, the same beingcarried by the base toggle member. The lever 50 is pivoted to arm 37 bythe threaded pivot member 51 and the respective ends 52 and 53 of themember, FIGURES 3 and 5, are engaged by the coil springs 54 which seatat their base in recesses provided for the purpose in the base togglemember.

The carriage yoke 25 has oscillating movement through an arc ofapproximately 170 degrees which compresses the coil springs 43 and 44-of the toggle arrangement by eccentric pivot action. The carriage yoke25 is shown in FIGURE 2 as being rotated in a clockwise direction andthe action of the coil springs at this point in the rotative movement isto maintain the base toggle member 34 positioned to the right and incontact with stop 21. As clockwise rotation of the carriage yokecontinues, the base toggle member will be yieldingly biased in adirection towards the left which causes the cam follower 42 to engagethe cam 31. This position of the parts is clearly shown in FIGURE 3 andit will be observed that the coil springs have been compressed to themaximum extent. Due to engagement of the cam follower 42 with the cam31, movement of the base toggle member 34 is prevented and said memberis held against movement until the carriage yoke reaches a releaseposition indicated by line X in FIGURE 2. When the release position isreached the cam 31 will be positioned just sufiiciently below the camfollower 42 as to free the toggle arrangement, and accordingly the fullcompressive force of the coil springs 43 and 44- is effective tooscillate the base toggle member 34 with a snap motion into its lefthand position, thus rotating the switch operating shaft 10 in acounterclockwise direction. The parts will thereupon assume the positionas shown in FIGURE 4- and wherein the member 34 is now in contact withthe stop 20.

For returning the base toggle member to a right hand position, thecarriage yoke is rotated in a counterclockwise direction from itsposition as shown in FIGURE 4. After the carriage yoke has reached andpassed a vertical dead center position, the action of the coil springswill be to resiliently bias the base toggle member in a right handdirection. However, the cam 30 will now be positioned in the path of thecam follower 41 and movement of the base toggle member will be preventedas clearly illustrated in FIGURE 5. As counterclockwise rotation of theyoke continues the coil springs will be additionally compressed and whenthe release position is reached as indicated by line Y of FIGURE 2, thebase toggle member will snap into its right hand position and returnrotation of the switch operating shaft takes place.

Referring again to FIGURE 4 it will be seen that with the parts in theposition as shown, the end 53 of the blocking lever 50 is positionedimmediately adjacent the cam 31. As long as the parts remain as shown inFIGURE 4, the cam 31 accordingly provides a stop preventing movement ofthe base toggle member in a clockwise direction towards the right. Thusit is impossible to inadvertently or accidentally rotate the switchoperating shaft and over-ride the toggle switch operator. In theopposite horizontal position of the carriage yoke similar action willnot take place, since the cam 30 is on the wrong side with respect tothe blocking lever for coaction therewith. However, in order to haveblocking action between the parts when the switch operator is in aposition opposite to that of FIGURE 4, it is only necessary to add asecond cam such as 30 to the arm 28' of the carriage yoke. This secondcam will thus be located I on the same side as cam 31 and the two camswill coact with the ends respectively, of the blocking lever in a manneras described. Since the blocking lever is pivoted it is thus capable ofoscillation. However, the coil springs 5'4 tension each end andresiliently maintain the lever in equilibrium. The switchmanautomatically disengages the blocking device when he rotates the shaft11 for another operation of the switch.

The invention is not to be limited to or by details of construction ofthe particular embodiment thereof illustrated by the drawings, asvarious other forms of the device will, of course, be apparent to thoseskilled in the art without departing from the spirit of the invention orthe scope of the claims.

What is claimed is:

1. In a device of the character described, the combination with a switchoperator shaft and an operating shaft for switch mechanism, of a togglearrangement including a base toggle member fixed to the operating shaftof the switch mechanism and a rotatable carriage yoke fixed to theoperator shaft, coil spring structure forming part of said togglearrangement and which is compressed by eccentric pivot action resultingfrom oscillating movement of the carriage yoke, at least one cam on thecarriage yoke, and at least one cam follower provided by the base togglemember and so located as to have opera tive coaction with the cam, saidcam follower engaging the cam when the yoke is oscillated in a certaindirection to prevent oscillating movement of the base toggle memberuntil the coil spring structure is compressed to substantially a maximumextent.

2. A device of the character as defined by claim 1,

additionally including a supporting frame which journals the operatorshaft and the switch operating shaft so as to permit rotation thereof,and wherein the supporting frame provides a pair of spaced stops forlimiting the oscillating movement of the base toggle member.

3. A device of the character as defined by claim 1, wherein two cams arelocated on the carriage yoke, one on each side member of the yoke, andwherein two cam followers are provided by the base toggle member forcoaction with the cams respectively.

4. A device of the character as defined by claim 1, additionallyincluding a supporting base member for the coil spring structure, meanspivotally mounting the said supporting base member on the base togglemember, and wherein said cam follower is located on the base togglemember at the pivot connection therewith of the supporting base memberfor the coil spring structure.

5. In a device of the character described, the combination with a switchoperator shaft and an operating shaft for switch mechanism, of asupporting frame having journalling portions, certain of said portionsmounting the operating shaft of the switch mechanism in a rotatablemanner, a base toggle member fixed to said operating shaft, a carriageyoke journalled by certain other portions of the supporting frame andbeing fixed to the switch operator shaft which assists in journallingthe carriage yoke, a spring supporting base member carried by the basetoggle member, coil spring structure confined between the supportingbase member and the carriage yoke to form a toggle arrangement with thebase toggle member, 21 pair of cams on the carriage yoke being locatedon respective side members of the same, and cam followers provided bythe base toggle member at the connection therewith of the springsupporting base member, at least one cam follower engaging one of thecams during oscillating movement of the carriage yoke in eitherdirection to prevent oscillating movement of the base toggle memberuntil the coil spring structure is compressed to substantially a maximumextent by eccentric pivot action resulting from said oscillatingmovement of the carriage yoke.

6. In a mechanical operator for electric switch mechanism, thecombination with a switch operator shaft and an operating shaft forswitch mechanism, of a supporting frame providing upright supportshaving journalling portions, certain of said portions mounting theoperating shaft of the switch mechanism in a rotatable manner, a basetoggle member fixed to said operating shaft and upon oscillatingmovement thereof producing rotation of the shaft, said operator shaftbeing mounted by another journalling portion for rotation, a carriageyoke supported for oscillating movements by the supporting frame andbeing fixed to the switch operator shaft which assists in journallingthe carriage yoke, a spring supporting base member pivotally carried bythe base toggle member, coil Spring structure confined between thesupporting base member and the carriage yoke to form a togglearrangement with the base toggle member, whereby the coil springstructure is compressed by eccentric action resulting from theoscillating movement of the carriage yoke, at least one cam on thecarriage yoke, and at least one cam follower provided by the base togglemember and located in alignment with the pivot axis of the springsupporting base member, said cam follower engaging the cam when the yokeis oscillated in a certain direction to prevent oscillating movement ofthe base toggle member until the coil spring structure is compressed tosubstantially a maximum extent.

7. A device of the character as defined by claim 6, additionallyincluding a pair of spaced stops on the supporting frame and located inthe path of the base toggle member for limiting the degree ofoscillating movement of said base toggle member.

8. A device of the character as defined by claim 6, additionallyincluding a pair of spaced stops on the supporting frame and located inthe path of the base toggle member for limiting the degree ofoscillating movement of said base toggle member, and a blocking leverpivoted to the supporting frame and adapted to coact With said cam, whenthe base toggle member is located in an oscillated position in contactwith one of said stops, to prevent accidental or inadvertent rotation ofthe operating shaft for the switch mechanism, said blocking lever andcam automatically disengaging when the operator shaft is rotated forelfecting a switch operation.

9. In a mechanical operator for electric switch mechanism, thecombination with a switch operator shaft and an operating shaft forswitch mechanism, of a toggle arrangement including a base toggle memberfixed to the operating shaft of the switch mechanism and a rotatablecarriage yoke fixed to the operator shaft, a supporting frame for thetoggle arrangement and which mounts the operator shaft and the switchoperating shaft permitting rotation, coil spring structure forming partof said toggle arrangement and which is compressed by eccentric pivotaction resulting from oscillating movement of the carriage yoke, atleast one cam on the carriage yoke, at least one cam follower providedby the base toggle member and so located as to have operative coactionwith the cam, said cam ollower engaging the cam when the yoke isoscillated in a certain direction to prevent oscillating movement of thebase toggle member until the coil spring structure is compressed tosubstantially a maximum extent, a pair of spaced stops on the supportingframe for limiting the oscillating movement of the base toggle member inboth directions, and a blocking lever pivoted to the supporting frameand adapted to coact with said cam when the base toggle member islocated in an oscillated position in contact with one of said stops, toprevent rotation of the operating shaft for the switch mechanism exceptby actuation of the operator shaft.

References Cited in the file of this patent UNITED STATES PATENTS659,946 Whittingham Oct. 16, 1900 1,602,871 Aalborg Oct. 12, 19261,855,804 Lucas Apr. 26, 1932 2,018,904 Taylor Oct. 29, 1935 2,533,743Sharp Dec. 12, 1950 2,614,186 Sutton et a1. Oct. 14, 1952

